There's something utterly fascinating about twins. Two babies sharing a womb only to come out looking the same– it isn't just the scientific world that's fascinated by this. Every human being has a slight curiosity about what goes on with those doubles. When they're identical, that curiosity goes up about 100%.
Most people aren't a twin. At the same time, most people have encountered twins. There was that set of twins at school (that nobody could tell apart). Anyone who watched Full House will remember Mary-Kate & Ashley Olsen as the cutest twins on TV. Monica and Chandler on Friends? They weren't exactly given much warning, but they welcomed twins.
By definition, twins are two offspring by the same pregnancy. Whether they're monozygotic or dizygotic turns scientific very quickly, but most people are more than aware of the difference– there's identical (and not).
The chances of having twins are actually significantly higher than most people think. With a 0.45% occurrence rate, that puts the chance of giving birth to twins at 1 in 250 births. The statistics are higher than the chances, though.
It's time to learn about twins. Here are 20 fascinating things to know about those babies that are double the trouble (but double the cute).
20 40% OF TWINS INVENT THEIR OWN LANGUAGE
Babble away to each other they might, but think twice before you call twin talk "meaningless babble." One of the most fascinating things about twins is their ability to communicate on a level that regular people just can't reach. Twins actually invent their own languages– inverted words and onomatopoeic expressions are part of it.
The Huffington Post reports that up to 40% of twins invent their own languages. Amazingly, although kind of sad, the languages don't tend to last into adulthood. The made-up twin language often disappears once the twins start learning a real language. This behavior has occasionally been recorded between babies who aren't twins.
19 TWIN BIRTHS ARE ON THE RISE (NOW ONE IN EVERY 30 BIRTHS)
Yup, twins are taking over. In 2012, a National Center For Health Statistics report outlined the sharp rise in twin births between the 1980s and late 2000s. Experts suggest that the number of women using fertility treatments might be a contributing factor.
Twin birth rates in the US rose 76% between 1980 and 2009. 1 in 30 babies born today is now a twin.
While twin births are up, the New England Journal of Medicine reports that triplets births actually lowered 29% between 1998 and 2011. Still, that's a lot more double strollers, twin high chairs, and matching PJs than ever before.
18 IDENTICAL TWINS DON'T HAVE IDENTICAL FINGERPRINTS
Facts like these are utterly fascinating. You'd think that twins coming from the same egg would share absolutely everything– after all, they look the same. Despite almost sharing the same DNA, identical twins do not have identical fingerprints. This is because fingerprints aren't solely based on DNA.
Amazingly, when twins are conceived, they do start out with the same fingerprints. Somewhere between 6 and 13 weeks into their womb development though, the babies move. They start to touch the amniotic sac. The Huffington Post reports that this is when the unique fingerprint ridges and lines result in different prints. #MindBlown
17 EATING DAIRY CAN INCREASE CHANCES OF HAVING TWINS
Let's be clear, here. Sitting there eating giant pots of yogurt and downing gallons of milk isn't going to magically give you twins. That said, enough scientific studies have been made to suggest that there is a link. A Journal of Reproductive Science study showed that women who eat more dairy are more likely to conceive twins.
Women who eat dairy are 5 times more likely to have twins than those who don't.
The reason? Cows produce IGF (an insulin-like growth hormone). That gets released into their system. Their milk eventually gets consumed by us, the humans. The study compared women eating dairy to vegan mothers.
16 TWINS COMMUNICATE IN THE WOMB (AND THEY DO IT TENDERLY)
What we'd give to have more knowledge of just what goes on in the womb. In 2011, Italian researchers studied 3D videos of twins in their mother's womb, so The Huffington Post reports. At 14 weeks of gestation, video footage showed twins reaching out to one another.
By the 18-week mark, twins were touching each other more than they touched their own bodies. The researchers concluded a positive on the fact that "twins [make] distinct gestures towards each other and were as gentle to the other twin's delicate eye area as they were when they touched their own." Adorable, right?
15 IT'S POSSIBLE FOR TWINS TO HAVE DIFFERENT FATHERS
These two daddies were holding their 4-month-old twin babies. Million Dollar Listing New York's Fredrik Eklund and Derek Kaplan are an example of how twins can have different biological fathers. When it's a traditional mom and dad birth though, the chances are one in a million.
In 2009, Mia Washington gave birth to twins with two different fathers– it took Dr. Hilda Hutcherson, Professor of Obstetrics and Gynecology at Columbia University to explain it. "Normally, a woman releases one egg each month. For Mia, there were two." If you're raising an eyebrow over what might have happened here, yes it did. But the result is still remarkable.
14 TALL WOMEN ARE MORE LIKELY TO HAVE TWINS
Science has taught us a lot. With each year, we discover new and amazing facts. One of those happens to be that tall women are statistically more likely to have twins. Long Island Jewish Medical Center's Gary Steinman, MD, Ph.D. discovered this after looking at the insulin-like growth hormone, IGF.
This isn't one you get much choice in the say of– it all has to do with having more insulin-like growth hormone.
"The more IGF a woman has, the greater chance she has of becoming pregnant with twins, because IGF governs the rate of spontaneous twinning," Dr. Steinman said. If you're super tall and pregnant, prepare for a possible double heartbeat.
13 MASSACHUSETTS HAS MORE TWINS THAN ANY OTHER STATE
This one is less about the science (and more about the simple stats). Interestingly, the US state of Massachusetts has the highest twin birth rate. Nearly 4.5 births out of 1000 are twins here. MA is followed by Connecticut and New Jersey. With all those states being in the New England or East Coast area, there's definitely a pattern.
Huff Post reports the reason being that more multiple births occur "in affluent towns outside Boston." Researchers point towards a higher concentration of women having children after they've pursued careers as the cause. That's a later pregnancy attempt, and more IVF attempts.
12 NIGERIA'S YORUBA PEOPLE HAVE THE HIGHEST GLOBAL TWIN RATE
African countries have much higher rates of twin births than any other continent. One country, in particular, is topping the charts. While the country of Benin ranks first with 27.9 twins per 1,000 births, the focus is sharply on Nigeria, where the Yoruba people have 45 to 50 sets of twins per 1000 births.
The high consumption of yams is said to be the cause– substances in them can cause the release of more than one egg.
The Culture Trip reports medics as listing diet to factor heavily in the outcome. Yams are said to produce the estrogen resulting in multiple births.
11 UP TO 22% OF TWINS ARE LEFT-HANDED (NORMAL RATE IS UNDER 10%)
In general, just under 10% of the population is left-handed. That's around 1 in 10 people. The figure changes massively in twins though, where Twins UK reports the incidence rate to be as high as 22%. There's a difference in rates between identical and non-identical twins, though.
The reasons are thought to be linked to cerebral symmetry. For the 20% of identical twins where one is right-handed and one if left-handed, Very Well Family points towards position in the womb determining handedness. This makes sense for twin pairs who are right and left-handed since they're likely to lie in opposing directions.
10 TWINS CAN ENTER THE WORLD IN DIFFERENT YEARS
Birthdays are a giant deal whether you're a twin or not. While the vast majority of twins have the same birthday, remember that it's technically possible for twins to be born in separate months (as well as years). Every Day Health used the example of a set of twins in Buffalo, NY. One was born at 11.37 p.m. on December 31st, 2011. His brother was born at 12.10 a.m. on January 1st, 2012.
It goes further, though. IVF treatment can determine when an embryo is implanted. One case saw a 5 year-old have a twin sister who was just 2 months old.
9 TWINS SEPARATED AT BIRTH "MISS EACH OTHER" (EVEN WHEN THEY DON'T KNOW)
Twins separated at birth will actually demonstrate a sense of missing their twin– even if they are completely unaware of their twin's existence. When Meredith Grace and Meredith Ellen Rittenhouse were separated at birth in China, their words were recorded by Every Day Health.
"I'm so lonely. I wish I had a sister." This came from a 2 year-old who didn't know that her twin had been separated from her at birth.
Those were one twin's words at the age of 2. At the age of 3, the same twin was asked what she wants to be when she grows up. Her reply was: "Sister."
8 THE WORLD'S OLDEST TWINS LIVED TO 107 AND 108 YEARS
We're so used to seeing pictures of twins as babies or children, it can easy to forget that twins age (just like the rest of us). The world's oldest twins were the Japanese-born Kin Narita and Gin Kanie. They lived to be 107 and 108.
The chances of identical twins living to be over 100 are 1 in 700 million. The oldest current living twins are British. They are Marian Warner and Nora Langton (although both shared the same maiden name before one was married). They were born in 1912, making them 106 years old. The top 10 oldest twin sets are all British or American, except one set from Italy.
7 MOTHERS OF TWINS MAY LIVE LONGER
In 2014, The Huffington Post shared an interesting set of studies that show mothers of twins living slightly longer. While an old study from the 1800s showed mothers of twins in Utah living longer because they were "strong and healthy" to begin with, there is some science to it.
Twinning is winning. A 2011 study showed that moms of twins do live longer.
"Twins could be an evolutionary adoption in which healthy moms take the chance to pass on double their genes at once," Live Science reports. The difference in life expectancy isn't huge, but the stats are definitely there.
6 TWINS CAN BE DIFFERENT RACES
Ready for something super scientific? Twins can legitimately be born as two different races, despite having parents from one race. One case got Every Day Health's attention. A Dutch couple, Wilma and Willem Stuart were surprised to welcome twin boys where one twin was white and one was black.
Heteropaternal superfecundation is what happens. This can be the result of botched fertilization. Essentially, this will occur in an IVF situation where another man's swimmers are accidentally mixed in with the actual father's. Not an ideal situation, but definitely an explanation for the surprise of having twins that are two different races!
5 TWIN PREGNANCIES ARE SHORTER (AVERAGING 37 WEEKS)
While this might sound like an interesting or exciting statistic, we will point out that the reason for multiple births generally resulting in shorter pregnancies is quite simply that premature births are more common.
Almost 50% of twins are born prematurely. A high amount also have a low birth weight. Full term for twins in the UK is considered to be 37 weeks, as opposed to the standard 39-40 weeks for single births. If you're expecting twins, your doctor will pay close attention to your overall well-being. They will also most likely alert you to the fact that a twin pregnancy is likely to be slightly shorter.
4 IN 1853, ONE PARENT HAD 8 TRIPLETS AND 8 TWIN SETS
We're used to seeing large families. 19 Kids and Counting had to have its title changed as the Duggar family continued to have more babies. There was also Nadya Suleman, also known as Octomom. While it's not unheard of for a woman to have twins more than once, one parent stands out in history.
A Russian man named Kirilow had 8 sets of triplets and 8 sets of twins– a total 72 children.
Twins UK documents this 1853 registration to come from one man. He had been married twice, but between his 4 sets of quads, 8 sets of triplets, and 9 sets of twins, the babies added up.
3 IF MOM IS A FRATERNAL TWIN, HER CHANCES INCREASE FOUR-FOLD
While these two identical twins are posing with their babies, statistics mean high chances of having twins as a fraternal (non-identical) twin. The chances rise to four-fold the norm if mom herself is a fraternal twin.
Other interesting statistics include the 17% increased chance of having twins for a woman aged over 45. Interestingly, Huggies also reports that women who are overweight are more likely to have twins. This could well be a result of obesity and fertility problems leading to fertility treatment (which increases the chances of multiple births). Your health should always come first. That's the most important thing to take away from this.
2 17 MINUTES IS THE AVERAGE TIME BETWEEN EACH TWIN DELIVERY (LONGEST WAS 84 DAYS)
Yes, pushing out one baby is hard enough as it is. When it's twins though, it's twice the effort. While the rest period between deliveries isn't exactly a vacation, it's reassuring to know the statistics. Remember though, that each delivery is different.
The average timespan between the first and second twin arriving is 17 minutes, Very Well Family reports. Additionally, it's worth noting that about 40% of twins are both born head-down. As to the longest timeframe every recorded between the first and second twin arrival, The Guinness Book of Records states this to be 84 days. Yup, November 11, 1995 and February 2nd, 1996 mark the longest interval ever.
1 SCARLETT JOHANSSON, ASHTON KUTCHER, VIN DIESEL, AND GISELE BUNDCHEN ARE ALL TWINS
Some celeb twins are obvious. Mary-Kate and Ashley Olsen are a set of twins whose entire career was built on being a #Twin. A lot more celebs out there are twins than you might think. Scarlett Johansson has a twin brother. So does Ashton Kutcher. The supermodel, Gisele Bundchen posted this pic of herself with her twin sister.
Other celeb twins include Friends' Giovanni Ribisi (Phoebe's brother), Vin Diesel, Benji Madden, and 007 James Bond's Eva Green. Fun fact. The writer of this article used to share a sandpit with Eva Green (sadly no memories of a twin). Keifer Sutherland is also a twin.